* {
    margin: 0;
    padding: 0;
}

body {
    height: 100vh;
    background-color:#827593;
}

body h1 {
    text-align: center;
    color:#fff;
    height: 80px;
    line-height: 80px;
}

.container {
    display: flex;
    flex-direction: column;
    align-items: center;
    width:500px;
    height:320px;
    margin: 100px auto;
    background-color:#e5e3e8;
}

.container .menu {
    display: flex;
    width: 300px;
    height: 85px;
    align-items: center;
    /* justify-content: center; 没必要使用此语句*/
}

.container .menu div {
    width: 100%;
    text-align: center;
}

.container .menu div span {
    /* 设置或检索在对象上移动的鼠标指针采用何种系统预定义的光标形状。 */
    cursor: pointer;
}

.container .clock {
    display:flex;
    align-items: center;
    width: 400px;
    height: 150px;
    justify-content: center;
    background-color: #5f546e;
    box-shadow: 0 0 40px rgba(0, 0, 0, 0.6);
}

.container .clock .clock-item {
    display:flex;
    position: relative;
    flex-direction: column;
    /* 使flex的子项在当前行的测轴方向上的对齐方式 */
    align-items: center;
    width:60px;
    margin: 0 30px;
}

.container .clock .clock-item div {
    font-size: 12px;
    color: #ccc;
}

.container .clock .clock-item span {
    font-size: 60px;
    font-weight: 100;
    color: #fff;
    /* 指定字符之间额外间隙 */
    letter-spacing: 5px;
}

.container .clock .clock-item:not(:last-child)::after{
    content: ":";
    position: absolute;
    top: 35%;
    right: -30px;
    font-size: 30px;
     color: #fff;
}

.toast {
    position: absolute;
  top: calc(60% - 25px);
  left: calc(50% - 100px);
  width: 200px;
  height: 50px;
  line-height: 50px;
  text-align: center;
  color: #fff;
  background-color: rgba(0, 0, 0, 0.6);
  opacity: 0;
  pointer-events: none;
}